<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    
    <script>
        class Animal{
            constructor(name){
                this.name = name
            }
            drink(){
                console.log(this.name +'在喝水')
            }
        }
        //子类 extend 父类
        class Dog extends Animal{
            constructor(name,age){
                super(name)
                this.age =age
            }
            eat(){
                console.log(this.name +'在吃骨头')
            }
        }
        const dog = new Dog('来福',8)
        dog.eat()
    </script>
</body>
</html>